Method and apparatus for micromachines, microstructures, nanomachines and nanostructures

ABSTRACT

Parts and structures are described for micro and nano machines and the creation of macro structures with nano and micro layers of special materials to provide improved performance.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a divisional of U.S. Pat. No. 6,813,937, issued Nov.9, 2004, which claims priority from U.S. Application No. 60/334,181,filed Nov. 28, 2001 by Victor B. Kley for “Cantilever, Nano & MicroParts, and Diamond Knives.”

This application is related to the following seven U.S. patentapplications, the disclosures of each other application is incorporatedby reference in its entirety for all purposes:

-   -   U.S. patent application Ser. No. 10/093,842, filed Mar. 7, 2002        by Victor B. Kley for “Nanomachining Method and Apparatus;”    -   U.S. patent application Ser. No. 10/094,408, filed Mar. 7, 2002        by Victor B. Kley for “Active Cantilever for Nanomachining and        Metrology;”    -   U.S. patent application Ser. No. 10/094,411, filed Mar. 7, 2002        by Victor B. Kley for “Methods and Apparatus for Nanolapping;”        and    -   U.S. patent application Ser. No. 10/228,681, filed Aug. 26, 2002        by Victor B. Kley for “Active Cantilever for Nanomachining and        Metrology.”

The following U.S. patents are incorporated by reference in theirentirety for all purposes:

-   -   U.S. Pat. No. 6,144,028, issued Nov. 7, 2000 to Victor B. Kley        for “Scanning Probe Microscope Assembly and Method for Making        Confocal, Spectrophotometric, Near-Field, and Scanning Probe        Measurements and Associated Images;”    -   U.S. Pat. No. 6,252,226, issued Jun. 26, 2001 to Victor B. Kley        for “Nanometer Scale Data Storage Device and Associated        Positioning System;”    -   U.S. Pat. No. 6,337,479, issued Jan. 8, 2002 to Victor B. Kley        for “Object Inspection and/or Modification System and Method;”    -   U.S. Pat. No. 6,339,217, issued Jan. 15, 2002 to Victor B. Kley        for “Scanning Probe Microscope Assembly and Method for Making        Confocal, Spectrophotometric, Near-Field, and Scanning Probe        Measurements and Associated Images;”    -   U.S. Pat. No. 6,752,008 issued Jun. 22, 2004 to Victor B. Kley        for “Method and Apparatus for Scanning in Scanning Probe        Microscopy and Presenting Results;”    -   U.S. Pat. No. 6,787,768 issued Sep. 7, 2004 to Victor B. Kley        and Robert T. LoBianco for “Method and Apparatus for Tool and        Tip Design for Nanomachining and Measurement;” and    -   U.S. Pat. No. 6,802,646 issued Oct. 12, 2004 to Victor B. Kley        for “Low Friction Moving Interfaces in Micromachines and        Nanomachines.”

The disclosure of the following published PCT application isincorporated by reference in its entirety for all purposes:

-   -   WO 01/03157 (International Publication Date: Jan. 11, 2001)        based on PCT Application No. PCT/US00/18041, filed Jun. 30, 2000        by Victor B. Kley for “Object Inspection and/or Modification        System and Method.”

BACKGROUND OF THE INVENTION

The present invention relates to micro-electromechanical systems (MEMS)and to Nano Electromechanical Systems (NEMS™). In particular, thepresent invention is directed to forming parts and structures for microand nano machines and the creation of macro structures with nano andmicro layers of special materials to provide improved performance.

In the foregoing listed related commonly owned issued patents andpending patent applications, various methods, apparatus, and techniqueshave been disclosed relating to micromachining and nanomachiningtechnology. In U.S. patent application Ser. No. 10/094,408, variouscantilever configurations are discussed, along with possible uses in thefabrication of very small machines. In U.S. patent application Ser. No.10/093,842, U.S. patent application Ser. No. 10/093,947, and U.S. patentapplication Ser. No. 10/094,411, tools and techniques for performingmicro and nano scale machining operations are discussed. In U.S. patentapplication Ser. No. 10/094,149, fabrication of MEMS components usingdiamond as a construction material to substantially eliminate stictionand friction is discussed.

The foregoing are fundamental technologies and techniques that can beused to pave the way to the world of the very small, where structuresand machines are measured at micron and nanometer scales. What is neededare improvements to existing tools to facilitate their manufacture andto enhance their performance. There is a need for additional tools tofacilitate the creation of ultra-small structures. Techniques anddevices are needed for making very small mechanical components andmachines such as micro and nano gears, bearings, journals, shafts,cutters, cams, cantilevers, pumps, simple, complex and planetary gearassemblies, latches, locks, calculators, angle drives, propellers,linear motion translators, unique diamond coatings arrangements forknifes and compensatory deformation of target surfaces to use thecoating induced stress to create the final form. It is desirable to haveuseful nanostructures that can be fabricated by these tools which canthen serve as building blocks for larger micromachines.

BRIEF SUMMARY OF THE INVENTION

An embodiment of a new smaller and improved cantilever MEMS design inaccordance with the present invention is provisioned with features tofacilitate the use of cantilever scanning probe microscopy. A cantileverdesign in accordance with the invention also facilitates the use toolssuitable for micro- and nano-scale operations. A mounting plate toovercome present manufacturing limits and improve the overall yields ofcantilever assemblies useful for direct nanomachining and metrology isdisclosed.

Also disclosed is a geared pump in which the components use propertiesof diamond and silicon to form a simple high pressure gear pump which iscapable of moving fluids from a reservoir chamber to and through verynarrow channels and passages. Such a pump overcomes the presentlimitations of silicon MEMS pumps including their inability to develophigh force (pressure) to overcome the Van der Waals and surface forcesthat inhibit fluid flow in narrow channels and passages.

In accordance with another aspect of the present invention, a diamondcoating can be used to impart a desired shape to a substrate. Further inaccordance with the invention, certain macro uses of a diamond coatingcan be applied to general surfaces to produces structures such asmicro-scale knives.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the remaining portions of thespecification and the drawings:

FIG. 1 is a schematic representation of a cantilever assembly inaccordance with an aspect of the present invention, showing aperspective view and a top view;

FIGS. 1A-1C show variations of bonding channels according to theinvention;

FIGS. 2 and 2A-2C show schematic representations of cantilever tipvariations in accordance with the present invention;

FIGS. 3 and 3A-3C are schematic representations of variations of thecantilever according to the invention;

FIG. 4 is a schematic representation of a cantilever mounting plateaccording to the present invention;

FIG. 5 is view of the mounting plate shown in FIG. 4 taken along viewline 5-5;

FIG. 6 is a schematic representation of gear pump according to an aspectof the present invention;

FIGS. 7A-7C are additional detailed views of the gear assembly shown inFIG. 6;

FIG. 8 illustrate the general steps for fabricating a knife edge inaccordance with an embodiment of the invention;

FIG. 9 schematically illustrates the shaping of a substrate according tothe invention; and

FIGS. 10A and 10B illustrate different knife-edge embodiments.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a perspective view and a top view of a cantilever assembly102. A main body 112 serves as a mounting portion of the cantileverassembly. A flexural member extending from the main body constitutes acantilever member 104. Recessed features 106 are formed in the main body112 and serve as bonding channels. In accordance with the invention, thesurface area of the cantilever assembly is no greater than three squaremillimeters (3 mm²).

The recessed features facilitate mounting the cantilever assembly to anintermediate mounting plate. In a particular aspect of the invention,the recessed features can provide reliable permanent bonding of thecantilever assembly to a larger support structure. Turn to FIGS. 1A-1Cfor a moment. The views shown in these figures are taken along view line1-1 in FIG. 1. These views highlight example profiles of the recessedfeature 106 according to the invention. In FIG. 1A, a schematicrepresentation of the interior surface 116 of the recessed featurerepresents a roughened surface. This can be formed by chemical etchingor reactive ion etching (RIE) techniques. The roughened surface providesincreased surface area and “nooks-and-crannies” to achieve a securebonding. For example, adhesives or solder or other flowable bondingmaterial can be dispensed within the recessed feature and becomesecurely attach to the roughened surface. This bonding system provides asecure bond without requiring the bonding material be applied past thetop surface 114 of the main body 112, thus avoiding interfering with thescanning probe microscopy operations.

FIG. 1B shows another variation of the recessed feature 106. This can beformed lithographically or by other known conventional techniques. Theprofile shows an opening into the recessed feature that has a dimension(D) smaller than an interior dimension (d) in an interior region 118 ofthe recessed feature. FIG. 1C shows a similar recessed feature thatmight have been formed using an isotropic etch process. In both casesthe opening dimension (D) is smaller than an interior dimension (d).Stated more generally, in accordance with these particular embodimentsof the invention, the opening 120 of the recessed feature at leastpartially occludes the interior region 118 of the recessed feature.

Returning now to FIG. 1 it can be seen that the recessed features 106form a contiguous T-shape. It can be appreciated that in otherembodiments, discontinuous recessed features can be formed. Theparticular pattern may be determined depending on the particularstructure of the cantilever assembly, or the particular environment ofthe scanning probe microscopy system.

To complete the discussion of the detail shown in FIG. 1, a lever arm104 extends from the main body 112. This structure is a flexible memberand constitutes the cantilever of the cantilever assembly 102. In oneembodiment of the invention, the cantilever is integral with the mainbody. For example, the cantilever assembly can be fabricated from asilicon on insulator (SOI) wafer. The cantilever 104 can be alithographically defined structure. It can be appreciated, however, thatthe cantilever can be a separately fabricated member that issubsequently attached to the main body during manufacture.

FIG. 2 schematically illustrates a cantilever 104 in accordance with anaspect of the invention. A recessed region 202 is formed into a majorsurface 214 a of the cantilever in an end portion of the cantileverdistal the main body 112. The recessed region can be used to as areceptacle or mount point for receiving a secondary object. As can beseen in the profile view of FIG. 2A, for example, the recessed region isshown as a bowl-shaped recess. However, such shape is not necessary. Therecess can be formed to take on a shape that is suitable for aparticular implementation.

The recessed region illustrated in FIG. 2 is shown with acircular-shaped outline. However, it can be appreciated that otheroutline shapes might be more suitable for attachment of a secondaryobject. The shape can be a substantially continuous form; e.g.,elliptical, ovoid, etc. The shape can be triangular, quadrangular,pentagonal, and in general any regular or irregular polygonal shape.

To facilitate the attachment of a secondary object, one or morealignment features can be formed on the surface 214 a. For example, FIG.2 shows four such alignment features 204 a-204 d, though additional orfewer features can be provided if appropriate. The side views shown inFIGS. 2A-2C illustrate that the features can be recessed features orraised features. For example, FIG. 2A shows that the features 204 b-204d are raised surface features. These can be formed, for example, byproperly masking the surface of the cantilever 104 and etching away alayer of the surface, leaving only the raised features 204 b-204 d andrevealing the surface 214 a. FIG. 2B shows that the alignment features204 b-204 d can be recessed features. FIG. 2C shows a mixture of raisedfeatures 204 b, 204 d, and recessed features 204 c, illustrating thatany combination of raised or recessed alignment features can be formed,if needed. FIG. 2C also shows a suitably formed through hole 222 whichcan further facilitate attachment of a secondary object.

FIG. 3 shows a cantilever exemplar according to another aspect of thepresent invention. The cantilever 104 may have a series of etchedthrough passages sufficiently large to ventilate the cantilever and thuspermit easy flow of air or other gases through the cantilever. One ormore perforations 302 or openings can be formed through the cantilever.The number, size, shape, and arrangement of openings can vary, dependingon the requirements. For example, increasing the air flow by use of thisventilation scheme can reduce the total air resistance can and thusimprove the Q or signal to noise ratio of the cantilever when used inresonant SPM scan such as non-contact scanning, intermittent contactscanning, or tapping mode scanning operations. Openings can be used toattain a desired flexibility (spring constant) in the cantilever. Theopenings may serve to reduce the mass of the cantilever, and so on. Thiscantilever design can improve signal to noise when certain ScanningProbe Microscopy methods are used in conjunction with the cantileversuch as resonant non-contact Atomic Force Microscopy, Lateral ForceMicroscopy, and Magnetic Force Microscopy.

FIG. 3A shows an opening formed through the major surfaces 214 a and 214b of the cantilever. FIG. 3B shows that the first opening 302′ can beout of alignment with respect to the second opening 302″, if aparticular need requires for such a configuration. Incidentally, FIG. 3Ashows another mixed combination of raised and recessed alignmentfeatures 204 b-204 d.

Perforations 302 can be formed such that the cantilever possesses alattice structure. FIG. 3C shows various cantilever structures 104 a,104 b, 104 c having varying patterns of openings 312, 322, 332,respectively. These cantilever exemplars illustrate that any pattern ofperforations can be provided to accommodate particular structural oroperating characteristics of the cantilever.

Incidentally, FIG. 3C shows alternative configurations of recessedregions and alignment features. Recessed regions 302 can be any shape;for example, the figure shows a elongate shaped recessed region and adiamond shaped recessed region. The recessed region can be off-center ornot. The figure shows a square-shaped through hole 322 as an example.The alignment features 322 can be asymmetrically arranged, or may noteven be required. It can be appreciated from the various illustratedexemplars any configuration of recessed regions and alignment featurescan be provided to accommodate a particular application.

Cantilever assemblies 102 can be fabricated on different sized wafers.The larger wafers tend to be thicker than smaller wafers. Standard wafersizes include 4, 6, 8, and 12 inch wafers, although non-standard waferscould be used. A larger wafer allows for higher production yields ofcantilever assemblies. Cantilever assemblies with large dimensions mayrequire a thicker substrate than a smaller sized cantilever assembly,thus requiring the use of thicker wafers. The result is a range ofthickness dimensions when a family of cantilever assemblies aremanufactured to accommodate different uses.

FIG. 4 shows a mounting plate 402 having a compensating recessed region412 formed in the plate. The compensating recessed region can beconfigured to accommodate dimensional differences among cantileverassemblies and by so doing can maintain a pre-selected positioning ofthe cantilever, measured for example from the backside of a cantileverrelative to a reference.

FIGS. 5A-5C show sectional views of the mounting plate 402 taken alongview line 5-5 in FIG. 4. A cantilever assembly (not shown) can bemounted on a principal surface 502 of the mounting plate. However, inaccordance with the invention, a recess is formed with a plurality ofinterior surfaces, e.g., surfaces 504, 506, and 508, configured toreceive cantilever assemblies of varying dimensions. These surfacescomprise the compensating recessed region 412 of the mounting plate. Thedimensions W₁, H₁ and W₂, H₂ of the receiving regions defined by thesurface can be determined depending on the range of dimensions of thecantilever assemblies to be accommodated by the mounting plate.

For example, FIG. 5B shows a cantilever assembly 102 a shown received inthe region partially defined by surfaces 506, 508 of the mounting plate402. The backside 214 b of the cantilever 104 is measured relative to areference surface, R. Typically, the measurement is made relative to asurface to be scanned. As a matter of convention the direction of themeasurement can be considered to be in the Z-direction. The distance isshown as Z₀. FIG. 5C shows a second cantilever assembly 102 b havingdifferent dimensions. The region partially delimited by surfaces 504 hasan appropriate width dimension to receive the larger cantilever.Moreover, the depth dimension (H₁) is such that the backside 214 b ofthe cantilever 104 b has a Z-direction measurement of Z₀.

Thus in operation, the body dimensions of a cantilever assembly can bechosen along with the dimensions of a recess in the mounting plate 402to place the back side of the cantilever in the same plane (relative tothe Z-direction) regardless of its overall part thickness withoutaffecting the overall operation of the entire instrument. It can beappreciated further that in addition to variations in part thicknessamong cantilever assemblies, variations in the Z-direction position ofthe cantilever 104 relative to its main body 112 among cantileverassemblies can be compensated for in the same manner by properlyadjusting the Z-direction dimension (H) of the corresponding receivingregion. Thus, standard wafer thicknesses such as 525 microns, 625microns etc. can be accommodated without affecting theinterchangeability of the instrument. It can also be appreciated thatnon-flat surfaces appropriately configured and dimensioned can be usedinstead of or in combination with the flat surface exemplars shown inFIGS. 5A-5C.

FIG. 6 schematically represents an illustrative embodiment of a highpressure gear pump MEMS according to an aspect of the present invention.A gear drive assembly 600 provides a driving force to actuate gears in agear box assembly 612. In the particular embodiment shown in the figure,the gear drive exemplar includes a translation section comprising aplurality of expanding members 602 arranged in a lattice-like structure.A gear rack 604 is provided at a distal end of the lattice structure.

In a particular embodiment of the invention, the fabrication of the geardrive 600 can be fabricated as disclosed in pending U.S. patentapplication Ser. No. 10/094,408. Briefly, the gear drive can be formedon a silicon on insulator (SOI) wafer. The upper surfaces 600 a and 600c are the silicon layer spaced apart by a layer of insulation (notshown) from an underlying substrate 600 b. The lattice structure can bedefined photolithographically. An isotropic etch process applied in theregions of the expanding members 602 can remove the underlyinginsulation layer thus creating a suspended lattice structure fixed at aregion A. The silicon layer is partitioned into two zones 600 a and 600c. A ground potential can be applied to one zone (e.g., 600 c) and avoltage source V can be applied to the other zone (e.g., 600 a). Areturn path segment of silicon 606 provides a return path for electriccurrent to complete the electrical circuit from the voltage source V toground. The flow of current will cause thermal expansion of thetranslation section (expanding members 602) due to heat generated by theflowing current. The expansion will occur in all directions, however,the geometry of the lattice structure will produce a more pronouncedexpansion in the direction along arrow 622. Removing the current willcause the translation section to contract as cooling occurs, again alongthe direction of arrow 622. Repeated application and removal of currentcan produce a reciprocal motion 622 of the gear rack 604.

A pump room 632 houses a gear assembly 612. The gear rack 604 engagesthe gear assembly to drive the gears (FIG. 7A) by the reciprocatingmotion 622 of the translation section. A fluid reservoir 616 provides asource of fluid which can be pumped through a suitably formed orifice614 in the direction F. Fluid can be provided from an external source tothe reservoir through an inlet 618. FIG. 6 represents the orifice 614 inschematic fashion, illustrating the principle of the fluid pump. It canbe appreciated that a suitable connection or channel can be provided todeliver the pumped fluid to a destination.

FIG. 7A shows a cutaway view of the pump room 632 view in the directionof view line 7-7 shown in FIG. 6. A pump casing 712 houses the gearassembly 612 in a pump chamber 714. This views shows a portion of zone600 c of the silicon layer. The gear assembly comprise a first gear 702a and a driven gear 702 b in mesh with the first gear. Each gear has agear shaft 704 a and 704 b, respectively which is supported on bearingjournals 716 formed on the silicon layer 600 c. The gear rack 604 isshown engaging the driven gear. The reciprocating motion 622 will causethe gears to rotate in a reciprocating fashion. To complete thedescription of the figure, the return path segment 606 is shown. Theareas of contact where the gears mesh form high pressure points, thusdefining a high pressure area 722 in that region.

FIG. 7B shows a cutaway view of the pump room 632 seen from the top. Itcan be seen that portions of material in zone 600 a and zone 600 c ofthe silicon layer serve as journal bearings 716 on which the gear shafts704 a and 704 b are supported. The journal bearings can be round orcylindrically shaped bearing surface, or V-shaped surfaces (e.g., 55°V-shapes). The gears 702 a and 702 b are placed on the journals withinthe pump chamber 714 of the pump room, allowing the gears to turnmultiple revolutions or less then one revolution, depending on thestroke length of the gear rack 604. In an particular embodiment, thegears can be inserted into journals formed in the pump chamber. The pumpcasing 712 can be provisioned with opposing journals and a suitablechannel to direct the high pressure flow can be placed over the pumpchamber. It can be appreciated, however, that many other arrangementsare possible.

From the top view, it can be seen that the chamber is in fluidconnection with the reservoir 616. Walls 714 a and 714 b of the chamber714 are closely spaced from the faces 706 a, 706 b respectively of gears702 a and 702 b, leaving substantially only the gear teeth being exposedto the interior volume of the chamber. A channel 724 fluidically couplesan opening 724 in the chamber 714 to the orifice 614. The channel in agiven particular embodiment can be directed as appropriate to some othersuitable structure or destination. The channel can be about 50 micronsto 1 nanometer in width.

Fluid from the reservoir is picked up by the gear teeth when the gearsrotate. The fluid is forced by the action of the gear teeth into thehigh pressure area 722. The channel 724 is aligned with respect to thehigh pressure area allowing the high fluid pressure present to escapevia the channel 724. The constrained spacing between the chamber walls714 a, 714 b and the gear faces 706 a, 706 b creates a region of highflow resistance, thus preventing significant flow of fluid back into thechamber from the high pressure region and ensuring a flow of fluidthrough the channel. It can be appreciated that the chamber walls do nothave to extend across the entire face of the gears. In the case of apump, it is sufficient that a region about the chamber opening 724 issufficiently covered as to restrict the flow fluid from the chamberopening back to the reservoir 714.

Referring to FIGS. 6 and 7A, it another aspect of the invention anescape mechanism (not shown) can be employed to selectively disengagethe gear rack 604 from the gear assembly 612, for example, by moving therack up and down (arrow 624). Thus, for example, the gear rack can beengaged during the forward (or reverse) stroke of the reciprocal motionand the disengaged during the reverse (or forward) stroke. This wouldcause each gear to rotate continuously in one direction. However, in thecurrently shown embodiment, the pump can be effective from just the backand forth rolling of the gears when no such escape mechanism is used.Also it can be appreciated that alternate drive mechanisms other thanthe described thermal mechanism can be used to drive the gear assembly.For example, a suitable electrostatic comb drive, a piezoelectric drive,or a piezoresistive drive, a rotating electrostatic motor, and othersimilar devices can be used. Incorporating an escape mechanism toproduce unidirectional gear rotation, however, can be useful in otherapplications.

FIG. 7C shows additional detail of the gears 702 a and 702 b comprisingthe gear assembly 612. In accordance with a particular embodiment of theinvention, the gears are made of an obdurate low stiction material 752(like diamond) interacting with another similar material or withsilicon. In the particular embodiment shown, each gear 732, 734 can be adiamond gear with integral shaft 732 a, 732 b fabricated usingnanolapping diamond coating techniques more fully discussed in pendingU.S. patent application Ser. No. 10/094,411 and in U.S. patentapplication Ser. No. 10/094,149. In accordance with the invention, eachgear has a maximum surface area less than 1 mm².

A diamond coating can also be provided onto a substrate to form tools.The generalized fabrication sequence shown in FIG. 8 diagrammaticallyillustrates a substrate 802 having a coating of diamond 812 formedthereon. The substrate material can be titanium (or some tungsten-basedcompound), titanium aluminum vanadium (or some other titanium-basedcompound), silicon, tungsten or any very low cobalt metal ceramiccarbide or nitride. The diamond coating can have a thickness of 1-20microns. An overcoat coating 804 can be provided on the diamond coating.The overcoat coating can be titanium or tungsten followed by an optionalbonding layer 822 (indicated by phantom lines) such as nickel and anoptional companion substrate of (typically) titanium 824 (also indicatedby phantom lines).

A diamond edge can be formed by performing a sharpening operation on thelayered structure. As the tough matrix material of metal(s) and/orceramic(s) is removed during the sharpening process the thin harddiamond film, which is already sufficiently thin as to be very sharp, isexposed for the cutting operation. The resulting diamond edge can thenserve as the leading surface used in a cutting operation. The qualityand sharpness of an edge depends on its hardness. The diamond layerprovides the material to present a superhard edge supported by a robustmatrix of tough metal(s) and/or ceramic(s), as indicated above.

Referring to FIGS. 10A and 10B for a moment, the resulting sandwich canresult in two kinds of knife. A first knife assembly 1052 illustrated inFIG. 10A comprises a diamond layer 1014 forming a very thin blade havinga sharp edge by virtue of the diamond layer being thin. The diamond edgecan be covered by a thin (1 to 3 micron) layer of titanium and/ortungsten.

Alternatively, a second knife assembly 1054 shown in FIG. 10B comprisesan optional thick substrate 1024 which can be glued or thermally bondedto the over coated titanium and nickel layer to form a rugged cuttingedge with the diamond layer 1034. In this particular embodiment, thediamond layer is rigidly protected in the middle of the knife assemblyby the metal layers. However, the metal must be carefully sharpened andshaped to insure that the diamond is properly exposed to serve as asuperhard edge.

Returning to FIG. 8, if the coated substrate 802 is too thin the diamondfilm may through shrinkage (or expansion) induce a warping effect on thesubstrate. The substrate can be preformed to exhibit a complementarywarped shape in order to compensate for the expected the warpage due tothe diamond layer. Alternatively, the substrate can be coated on theback of the side to provide a reverse warping effect (bending forces inthe opposite direction) and then coated with titanium or tungsten.

Depending on the coating material and its expansion coefficient withrespect to the surface to be coated, it is possible to selectivelyproduce either an expansion induced warp or a contraction induced warp.For example, suppose a non-expanding or low-expansion rate glass iscoated onto a high expansion piece of copper at an elevated temperatureT_(A). Then as the system cools, the contracting copper will compressthe glass and may bend or shatter it. If the glass bond and the glass isweak enough (thin enough) and the copper relative to the glass is strongor thick enough, the glass may curve its edges inward toward the coppercenter. In the case of diamond on silicon, a very thin layer diamond(for example, a diamond layer a hundred times thinner than the siliconsubstrate) can cause bending of the silicon toward the center of thediamond layer as the materials cool, due to different coefficients ofexpansion of diamond and silicon, and due to the very high molecularbond strength diamond as compared to the bond strength of silicon.

FIG. 9 schematically illustrates this aspect of the invention with ageneric “pre-shaped” substrate that is suitable for deposition of adiamond layer to produce a desired shape (or surface contour) whiletaking into account the thermal cooling induced warping effect ofdiamond layer. A starting substrate material 902 can be formed topossess a predefined shape or surface contour. It can be understood thatthe pre-shaping can be performed by any of a number of conventionaltechniques; e.g., machining, grinding, chemical etching, and so on.

It is noted that the starting substrate material needs not bepre-stressed. However, it can be appreciated that a pre-stressing stepcan be performed so that when the re-shaping takes place, the stress ofthe re-shaped substrate can be compensated, either by adding more stressor reducing it as needed for a particular application.

A diamond deposition 922 step is performed to produce a diamond layer912 atop the substrate. Techniques for forming a suitable coating ofdiamond are known. As can be expected, the diamond layer will stress thesubstrate 902 as it crystallizes, thus pulling the pre-shaped form ofthe substrate 902 into a new shape 902′. It is noted that the finalshape need not be a flat surface, though a flat surface may bedesirable. It can be appreciated that any desired surface contour can beachieved by properly pre-shaping the starting substrate material anddepositing the diamond layer and varying its thickness to obtain acertain degree of re-shaping effect.

It can be appreciated that additional diamond layers can be provided tofurther effect shaping of the surface contour due to the warping effectof the diamond layers. For example, a diamond coating can be depositedon a first surface of the substrate, followed by another diamond coatingdeposited on the surface opposite the first surface, to compensate forthe warping of the first diamond layer. Selected areas on a first sideof substrate can be treated to form one or more diamond coatings atthose selected surface areas, to effect control of contour shape.

1. A cantilever assembly suitable for use in a scanning probe microscope(SPM) comprising a holder and a lever extending from the holder, thelever having a first major surface and a second major surface spacedapart from the first major surface and in parallel relation to the firstmajor surface, the lever further having an end portion distal theholder, the end portion having a recessed region formed on the firstmajor surface, the recessed region being suitable for receiving anobject or serving as a mount point for an object, the lever furtherincluding one or more openings formed through the first major surfaceand the second major surface.
 2. A cantilever assembly suitable for usein a scanning probe microscope (SPM) comprising a holder and a leverextending from the holder, the lever having a first major surface, thelever further having an end portion distal the holder, the end portionhaving a recessed region formed on the first major surface, the recessedregion being suitable for receiving an object or serving as a mountpoint for an object, wherein the lever is ventilated.
 3. A cantileverassembly suitable for use in a scanning probe microscope (SPM)comprising a holder and a lever extending from the holder, the leverhaving a first major surface, the lever further having an end portiondistal the holder, the end portion having a recessed region formed onthe first major surface, the recessed region being suitable forreceiving an object or serving as a mount point for an object, whereinthe holder includes a major surface having at least one recessed featureformed therein, the recessed feature having an opening that at leastpartially occludes an interior region of the recessed feature.